Method and apparatus for inflating and sealing packing cushions with rotary sealing mechanism

ABSTRACT

An apparatus for inflating and sealing packing cushions has a drive mechanism for feeding a preconfigured film material to a sealing mechanism in a flattened state without wrinkles in the sealing region in which a longitudinal seal is formed. In one aspect, the drive mechanism comprises a pair of upper adjacent belts and a backing element, such as a lower belt. The sealing mechanism may be a rotary sealing wheel that contacts the film material between the upper adjacent belts.

CROSS REFERENCE TO RELATED APPLICATION

This application claims priority under 35 U.S.C. §119(e) to ProvisionalApplication No. 61/093,858, filed Sep. 3, 2008, the disclosure of whichis hereby incorporated by reference in its entirety.

DESCRIPTION OF RELATED ART

Air-filled pillows or cushions may be used as a packing material andvoid filler in shipping cartons and the like. Such cushions typicallyhave two layers of plastic film material which may be sealed together toform chambers that are filled with air or other suitable gas. Thecushions are usually made from a long roll of material which typicallyhas a longitudinal direction along the film and a traverse directionacross the film. The film may be made of plastic or other suitablematerial known in the art. The film may be supplied and stored in rollsor in boxes. Typically, the film includes perforations which may bedisposed generally in the transverse direction across the film, but mayalso be located in other orientations such as diagonally. Theperforations may be variously configured such as between one or moresuccessive ones of the cushions so they can be torn apart or otherwiseseparated.

Although very light in weight, air-filled cushions take up a substantialamount of space. To reduce the volume of material which must be shippedand stored, such cushions are commonly made at or near the point of use.To avoid the need for packers and shippers to have large, complexcushion making machines in their facilities, suppliers of air-filledpacking cushions often provide their customers with film materials inwhich the major seals and perforations have already been formed(hereinafter referred to as “preconfigured film material”).

Packers and shippers who use preconfigured film materials are providedwith relatively inexpensive and easy-to-use machines for inflating andsealing the materials to complete the cushions at or near the point ofuse. Many machines are equipped with an elongate guide member which isinserted into a longitudinally extending channel in the film for guidingthe film through the machine. In some machines, the guide includes anozzle for injecting air into the cushion chambers. In other machines,air is injected from an injector separate from the guide. Examples ofmachines in which air is injected into cushion chambers through anelongate guide member include U.S. Pat. Nos. 6,209,286, 6,659,150,6,410,119, 7,174,696, and 7,325,377, all to the present assignee, thedisclosures of which are incorporated herein by reference. Examples ofmachines in which inflation gas is injected into an open edge of a filmor through perforations are shown in WO 00/43198, WO 00/43270, and U.S.Pat. Nos. 5,873,215 and 6,375,785, each owned by the present assignee,the disclosures of which are incorporated herein by reference.

SUMMARY OF THE INVENTION

The present invention is directed to a method and apparatus for makingair-filled packing cushions from a preconfigured film material. In oneaspect, a drive mechanism is configured to present a preconfigured filmmaterial to a sealing mechanism in a flatten state without wrinkles inthe sealing region of the film material in which a longitudinal seal isformed. The drive mechanism may comprise a pair of upper adjacent beltsand a backing element, such as a lower belt. The sealing mechanism maycontact the film material in the sealing region to produce a highquality longitudinal seal with significantly reduced instances ofburning, pinhole leaks, and weakly bonded seals that typically resultfrom film wrinkles

In one aspect, the sealing mechanism may be a rotary sealing mechanismcomprising a source of heat and a rotary sealing element. The rotarysealing mechanism may include a wheel made from a thermally conductivematerial, such as aluminum. The rotary sealing mechanism, together withthe drive mechanism, may facilitate significantly higher productionspeeds than are possible with conventional air cushion machines.

One or more of the mechanisms for feeding, driving, inflating, andsealing the film may be made adjustable such that the device is capableof processing a wide (and potentially unlimited) variety ofpreconfigured film materials, e.g., film materials having differentlysized and/or differently configured chambers. Operation of these variousmechanisms may be coordinated with a controller. In some aspects, thecontroller may identify the type of film without the need for operatorinput (e.g., using RFID technology or the like), and automaticallyaffect any needed adjustment of operation parameter(s) appropriate forthe type of film used.

In some embodiments, the preconfigured film material may include alongitudinally extending channel and inflatable chambers whichcommunicate with the channel. In these embodiments, the film materialmay be fed onto an elongate member which may be positionable in thelongitudinally extending channel and configured to have inflation gasintroduced into the chambers using a separate or integral injector toinflate the cushions. In alternative embodiments, a film material mayhave an open edge into which an inflation gas is injected from aninjector.

While certain aspects of the invention have been called out specificallyin the Summary of the Invention for illustrative purposes, additionalaspects of the invention are defined below in the remaining portions ofthe specification. The aforementioned aspects of the invention and theadditional aspects of the invention detailed below may be utilized inany suitable combination and subcombination.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will now be described in more detail withreference to preferred embodiments of the invention, given only by wayof example, and illustrated in the accompanying drawings in which:

FIG. 1 is a plan view, partly broken away, of a preconfigured filmmaterial usable for making air-filled packing cushions.

FIG. 2 is a perspective view of an apparatus for inflating and sealingair-filled packing cushions as described in U.S. Pat. No. 7,174,696.

FIG. 3 is an exploded perspective view of the apparatus shown in FIG. 2.

FIG. 4 is a fragmentary side elevation view of the sealing unit in theapparatus shown in FIG. 3.

FIG. 5 is a fragmentary cross-sectional view of the sealing unit of FIG.4.

FIG. 6 is an operational view of the apparatus of FIG. 2 transforming apreconfigured film material into air-filled packing cushions.

FIG. 7 is a plan view of another a preconfigured film material usable inmaking air-filled packing cushions.

FIG. 8 is a front perspective view of an apparatus for inflating andsealing air-filled packing cushions.

FIG. 9 is an exploded view of the sealing mechanism of the apparatusshown in FIG. 8.

FIG. 10 is a cross-sectional view of the sealing mechanism and inflationmechanism of the apparatus shown in FIG. 8.

FIG. 11 a is a rear perspective view of the apparatus shown in FIG. 8;FIG. 11 b is an exploded view of a sealing mechanism actuator.

FIGS. 12 a and 12 b illustrate an example of a rotary sealing mechanism.

FIG. 13 shows a preconfigured film material having an open edge throughwhich the chambers can be inflated.

FIG. 14 is an alternative preconfigured film material having an openedge through which the chambers can be inflated.

FIGS. 15 a-15 c illustrate a mechanism for controlling tension on a filmsupply roll during unwinding; FIG. 15 b is an exploded view thereof; andFIG. 15 c is a cross-sectional view thereof

FIG. 16 is a schematic illustration of a film edge guide.

FIG. 17 is a side elevation view of the apparatus shown in FIG. 8,illustrating the curved surface of the support element 214 in accordancewith one aspect of the invention.

FIG. 18 is a front perspective view of an apparatus for inflating andsealing air-filled packing cushions in accordance with an alternativeembodiment of the invention.

FIG. 19 is a rear perspective view of the apparatus of FIG. 18.

DETAILED DESCRIPTION OF THE INVENTION

According to one aspect of the invention, an apparatus for inflating andsealing packing cushions has a drive mechanism capable of presenting apreconfigured film material to a sealing mechanism such that the filmmaterial is in a flatten state and free or substantially free ofwrinkles in the sealing region, e.g., the area of the film in which alongitudinal seal is formed to trap inflation gas in the chambers. Inone embodiment, the drive mechanism comprises a pair of upper adjacentbelts and a backing element, such as a lower belt. The sealing mechanismmay contact the film material in an area of the film positioned betweenthe upper adjacent belts.

Terms such as “upper” and “lower” are used herein for illustrativepurposes and ease of reference. It should be recognized that such termsare not limiting, as the orientation of the various elements as well asthat of the overall apparatus may vary from that described hereinwithout departing from the scope of the invention.

FIGS. 8-12 illustrate an example of an apparatus 200 for inflating andsealing packing cushions in accordance with the present invention. Theapparatus 200 is relatively compact and is adapted to be convenientlyplaced on a table top or other surface, such as a custom stand (notillustrated). The apparatus 200 can be constructed of a lightweightmaterial such as a durable plastic or light metal. With reference toFIG. 8, the apparatus 200 includes a frame having a base 202 and avertical wall supporting a mandrel 205, a sealing mechanism having abelt drive assembly 218, and an adjustable speed blower 225 forsupplying air to an air injector 210. The mandrel may contain a roll ofpreconfigured film material (shown in shadowed area).

In one aspect, upper and lower film edge guides 257 a and 257 b,respectively, may be provided for aligning the film with the inflationand sealing mechanisms. As shown in FIGS. 8 and 10, the upper and lowerfilm edge guides 257 a and 257 b are separated by a relatively narrowgap through which the edge portion of the film material is fed to theinflation and sealing mechanisms. As inflation gas is injected into thefilm material, the chambers are inflated such that the height of thechambers becomes greater than the gap between the upper and lower filmedge guides 257 a and 257 b. This is illustrated in FIG. 10, where the“V” shape in the left-hand portion of the film 1 represents the inflatedchambers. The inflated chambers assist in keeping the film material in aflatten state as it is fed through the inflation and sealing mechanismsby resisting lateral movement of the film material through the gapbetween the film edge guides 257 a and 257 b. An optional guide roller255 also may be provided. As shown in FIG. 8, the guide roller 255 maybe positioned in approximately the same vertical plane as the mandrel205. As the film is unwound from the mandrel, an edge portion of thefilm passes over the guide roller 255 toward the belt drive assembly218. The guide roller 255 thereby provides a constant film path to theinflation and sealing mechanisms as the roll of material depletes. Asshown in FIG. 16, the axis B of the guide roller 255 may be offset withrespect to the axis A of the mandrel 205, e.g., at an angle ofapproximately 30-45 degrees. As the film 1 passes over the guide roller255, the offset axis B causes the edge of the film 1 to be raisedsomewhat, which tensions the film as it is guided toward the inflationand sealing mechanisms.

The mandrel 205 may be equipped with a clamping mechanism (not shown)for securing a roll of film. The clamping mechanism may include a handlethat is movable between a disengaged position, e.g., where thelongitudinal axis of the handle is generally parallel to the axis of themandrel 205, to an engaged position, e.g., where the axis of the handleis generally perpendicular to the axis of the mandrel 205.

The apparatus 200 also may have a perforation tear unit 250. An exampleof a perforation tear unit is described in commonly owned U.S. Pat. No.7,343,723 B2, the disclosure of which is hereby incorporated byreference. The perforation tear unit 250 includes a pair of nip rollersthat can be actuated to partially tear the film along the laterallyextending perforations to assist an operator in separating inflatedcushions or groups of inflated cushions from each other. Alternatively,a sheeting unit may be provided which completely tears the film alongthe lateral perforations to separate inflated cushions or groups ofinflated cushions from each other. As discussed more fully below,perforation tear unit 250 or sheeting unit may be associated with acontroller for automatically tearing the film along the perforationsafter inflating a predetermined number of cushions. This way, theapparatus 200 can be programmed to produce inflated film segments of adesired length (e.g., having one, two, three, four, five, six, or moreinflated cushions).

FIG. 9 is an exploded view of the belt drive assembly 218 and sealingmechanism 216 of the apparatus shown in FIG. 8. The belt drive assemblycomprises a pair of adjacent upper belts 218 a and 218 b and a lowerbelt 218 c. Upper and lower drive rollers 222 are driven by a motor forrotating the upper belts 218 a and 218 b and the lower belt 218 c. Arotary sealing mechanism 216 is positioned such that a sealing element216 a contacts the film in a sealing region located between the twoupper belts 218 a and 218 b to form a longitudinal seal to trapinflation gas in the chambers. A support surface 214, which may be ablock constructed from aluminum or other metal, is positioned underneaththe lower belt 218 c to provide an anvil surface against which the lowerbelt 218 c is deflected by pressure from the sealing mechanism 216.

FIG. 10 is a cross-sectional view showing the rotary sealing mechanism216 which has a relatively narrow convex portion forming a sealingelement 216 a around its circumference; the guide/air injector 210; thesupport surface 214; and the upper 218 a, 218 b and the lower 218 cdrive belts. The open “V” shape in left-hand portion of the film 1 asshown in FIG. 10 represents the chamber into which the inflation gas isinjected. The right-hand portion of the film 1 as shown in FIG. 10 isthe longitudinal channel into which the guide 210 is inserted. In thisembodiment, the guide 210 also functions as an air injector bydischarging air (or other inflation gas) through one or more openingslocated at or near the distal end of the guide 210. In otherembodiments, an injector separate from the guide may be used to injectinflation gas into the chambers. A knife blade may be located along theguide 210 for slitting the film to permit continued movement of the filmpast the sealing area. The inflated cushions are heat-sealed as the film1 passes between the sealing mechanism 216 and the lower drive belt 218c.

In another aspect, one or more of the drive belts may be crowned toassist in maintaining the film material in a flattened state in thesealing region as it is fed through the sealing mechanism. For example,as illustrated in FIG. 10, the drive belts 218 a, 218 b, and 218 c maybe crowned such that the sealing region of the film 1 (e.g., the portionof the film 1 positioned directly below the sealing element 216 a) israised relative to the adjacent portions of the film 1. Alternatively,the belts 218 a, 218 b, and 218 c may be crowned in a different (e.g.,opposite) configuration that functions to flatten the film 1 in thesealing region by pulling the film 1 outwardly relative to the sealingregion. The crowned drive belts 218 a, 218 b, and 218 c present the filmto the sealing mechanism 216 in a smooth, flattened state withoutwrinkling of the film material. This enables the sealing element 216 ato produce a longitudinal seal with significantly greater quality andprecision, and with significantly lower instances of burning compared toseals formed using conventional air cushion machines. The combination ofthe rotary sealing mechanism 216 and the drive belt assembly 218 alsoenables the device to operate at significantly higher production speeds,e.g., as high as 120 feet/minute or more. Conventional air cushionmachines employing a sealing rod, for example, typically are limited toproduction speeds of no more than about 70 feet/minute due to the slowheat transfer rate through the sealing belt and the high frictioncreated between the rod and the belt.

In another aspect, as illustrated in FIG. 17, the surface of the supportelement 214 may be curved in the direction of the film path. The apex ofthe curve may be located at approximately the center of the supportelement 214, e.g., where the sealing mechanism 216 contacts the filmmaterial. The curved surface of the support element 214 effectivelylengthens the path of the film material, which helps to compensate fordimensional changes in the film material as it is processed. Inparticular, the length of the film material is decreased somewhat as thechambers are inflated (due to expansion of the film material in thethickness direction). However, the edge portion of the film materialthat is sealed by the sealing mechanism 216 is not inflated, and thusthe length of the edge portion is not decreased as the chambers areinflated. As a result, the edge portion of the film material is prone togathering as the chambers are inflated, e.g., in an “accordion” fashion.The curved surface of the support element 214 increases the length ofthe film path, which assists in maintaining the film material in aflattened state as it is fed through the sealing mechanism 216.

As illustrated in FIG. 10, each of the drive belts 218 a, 218 b, and 218c may have a rib 219 a, 219 b, and 219 c, respectively, (e.g., ofrectangular cross-section) running along its length on the surfaceopposite the film-contacting surface. The ribs 219 a, 219 b, and 219 cmay engage corresponding grooves in the drive rollers 222 to guide andprevent slipping of the drive belts 218 a, 218 b, and 218 c along thedrive rollers 222. In the case of the lower drive belt 218 c, the rib219 c also further assists in straightening the film in the sealingregion. In particular, the rib 219 c on the lower drive belt 218 c maybe aligned with the sealing element 216 a such that when the sealingelement 216 a presses the lower belt 218 c against the support surface214, the rib 219 c creates a reactive force which deflects the lowerbelt 218 c to straighten the film in the sealing region.

In the embodiment shown in FIGS. 8-12, the lower belt 218 c is used as abacking element for the sealing mechanism 216. As used herein, the term“backing element” refers to the structure that contacts the filmmaterial opposite the sealing mechanism. The backing element typicallyis constructed of a resilient material, e.g., natural rubber or asynthetic rubber such as silicone rubber. The resilient surface conformsin part to the sealing element 216 a, which improves seal quality andincreases seal dwell time. When a resilient backing element is used, asupport element such as block 214 usually is used as an anvil surface,as previously described. Non-limiting examples of support elementsinclude drums, plates, wheels, boxes, and other surfaces constructedfrom metal or other rigid material. The support element may have aresilient material applied to one or more of its surfaces to function asa backing element. For example, a backing element can be formed byvulcanizing a ¼ inch layer of rubber onto an aluminum or steel wheel orother support element. Alternatively, a backing element can bepreconfigured as a resilient band and stretched over a backing element.The thickness of the backing element usually ranges from about ⅛ toabout ¼ inch. The resilient material should be selected such that thefilm material does not unduly stick to the backing element. Also, theresilient material should be selected such that it does not degradeunder heat. Suitable resilient materials often have a Shore A hardnessof from about 20 to about 95 durometer, usually from about 45 to about75, and more usually from about 50 to about 70. For example, a siliconerubber of 60 durometer may be used.

The sealing mechanism 216 may be mounted such that its axis is fixedrelative to the sidewall of the frame 202, or such that it isdisplaceable toward and away from the support surface 214, eithermanually or by mechanical assistance. It may be desirable to retract thesealing mechanism 216 away from the film 1, e.g., when operation of theapparatus is interrupted so as to prevent burning of the film 1. Asshown in FIGS. 11 a and 11 b, a linear stepper actuator 230 may be usedfor adjusting the position of the sealing mechanism 216. The position ofthe sealing mechanism 216 also may be adjusted for increasing ordecreasing the pressure between the sealing element 216 a and the lowerdrive belt 218 c. For example, the actuator 230 may cause the sealingmechanism 216 to be displaced such that springs 233 are compressed ordecompressed to create more or less seal force, respectively. Sealingpressure can be adjusted, for example, to accommodate films of differentthickness. As an alternative to a linear actuator, sealing pressure canbe made adjustable by providing a thumb screw or the like for adjustingthe position of the sealing mechanism 216 and/or backing element andwithout requiring significant disassembly of the machine or replacementof parts.

In the embodiment illustrated in FIGS. 8-12, the sealing mechanism 216is freewheeling, e.g., is caused to rotate by the movement of the film 1against which the sealing element 216 a is pressed. As previouslydiscussed, the upper belts 218 a and 218 b and the lower belt 218 c, allof which are driven by feed rollers 222, cause the film 1 to beadvanced. As an alternative to a freewheeling sealing mechanism 216, amotor may be provided for rotating the sealing mechanism in coordinationwith the other driving mechanisms.

FIGS. 12 a and 12 b show an exploded view of the sealing mechanism inthe apparatus of FIG. 8. A high temperature resistant bearing or bushing262 fits into a hardened aluminum wheel 216. The bushing 262 ispositioned over a stainless steel core body 264. Three heating elements270 and a thermocouple 266 are positioned in openings in the core body264. The components are secured together with a core body end cap 260and a core mounting shaft 272.

FIGS. 15 a-15 c illustrate a mechanism that may be used for controllingtension on the roll of film as it is unwound from the mandrel 205. Thetension control mechanism includes a linear actuator 280, an actuatorshaft 281, a nip roller 282 having a rubber surface, and a compressionspring 284. The nip roller 282 contacts the outer surface of the roll offilm as it unwinds. The linear actuator 280 causes the actuator shaft281 to be displaced, thereby compressing or decompressing spring 284 toincrease or decrease the amount of drag between internal disks and thehub of the nip roller 284. It may be desirable to control tension on theroll of film for a number of reasons. Tension on the film roll affectsthe presentation of the film to the inflation and sealing mechanisms,and the optimal amount of tension may vary for films having differentcushion sizes and/or configurations. The tension control mechanism alsomay be used as a brake to stop unwinding of the film roll when operationof the machine is interrupted. The linear actuator 280 may be controlledby a suitable controller to adjust unwind tension in coordination withoperation of the drive mechanisms and/or in response to characteristicsof the film material that are either manually inputted into the deviceor automatically sensed by RFID technology as discussed more fullybelow.

The inflation and sealing apparatus may have any of a number ofdifferent configurations, several examples of which are described below.The preconfigured film material can have various configurations, such ashaving seal lines defining generally rectangular chambers as shown inU.S. Pat. No. 7,090,912 to Perkins et al. or U.S. Pat. No. 6,582,800 toFuss et al., or undulating seal lines defining non-rectangular chambers,e.g., as shown in U.S. Pat. Nos. 6,410,119 and 6,761,960 to De Luca etal. By way of example, FIG. 1 shows a film having two layers 12, 13 of asuitable film material such as a polymer material including suchmaterials as high density polyethylene or low density polyethylene. Forexample, the films may include any suitable polyolefin including, forexample, a low density polyethylene, a homogeneous ethylene/alpha-olefincopolymer such as a metallocene-catalyzed ethylene/alpha-olefincopolymer, a medium density polyethylene, a high density polyethylene, apolyethylene terephthalate, a polypropylene, a nylon, a polyvinylidenechloride including one or more of a methyl acrylate or vinyl chloridecopolymers of vinylidene chloride, polyvinyl alcohol, polyamide, or anysuitable combination of the foregoing. Depending on the variousapplications, these films may have any suitable thickness such as fromabout 0.05 to about 25 mils. In most environments, the films will bebetween about 0.5 and 4 mils thick.

The material can be in the form of flattened tubing which is joinedtogether, or closed, along both of its longitudinal edges 16, 17, or itcan be open along one or both edges.

In the film material shown in FIG. 1, a single elongated sheet, orstrip, of film material is formed, for example, by slitting an extrudedbubble or by folding a web of material along its centerline to form edge16. Other methods may be used for preparing the film material, such asby heat sealing overlying webs. The opposite edge 17 may be closed oropen. In one embodiment, edge 16 is closed and edge 17 is open.

Again referring to FIG. 1, the two layers of film may be sealed togetherto form a longitudinally extending channel 19 and any number of suitablyconfigured inflatable chambers 21, 22. The channel 19 may be variouslyconfigured along one or both edges and/or along the middle of the film.Where the channel extends longitudinally near one edge of the material,one or more chambers 21, 22 may be arranged in a generally transversedirection across the material either in a perpendicular direction to thechannel or in an angular direction to the channel. Inlet openings 23 maybe configured to extend between the channel 19 and one of the chambers.In these embodiments, it may be desirable for the openings 24 tointerconnect the chambers. Optionally, a plurality of outlet ports 25may be included to permit excess air to escape from the channel 19during inflation and sealing. Where outlet ports are included, they mayextend between channel 19 and the edge 17 of the material. The edge 17may be unsealed in the region of the outlet port 25 to permit excess airto escape through the open edge 17. Alternatively, the edge 17 can besealed, in which case excess air may be permitted to escape throughperforations 26 extending laterally across the channel 19 and/or throughthe outlet ports 25. Other variations are possible. For example, someoutlet ports 25 may be open at the edge 17 and other outlet ports 25closed at the edge 17.

Optionally, generally transverse or diagonal rows of perforations 26 mayextend about across the film between the chambers of successive cushionsor groups of cushions to facilitate separation of the material eitherbefore or after the chambers are inflated. Alternatively, theperforations 26 can extend through the inflatable chambers 21, 22 and/orthe outlet openings 25 to separate groups of cushions.

In the film material illustrated in FIG. 7, each cushion 90 may have oneor more full-size chambers 91 and optionally two or more partial-sizechambers 92. The full-size chamber may be alternatively configured tohave any number of discrete sections 93 (e.g., four) which may bepositioned side-by-side across the film material, with openings 94between them. Each half-size chamber may also have any number ofsections 96 (e.g., three), with openings 97 between them.

Inlet openings 98, 99 may extend laterally between a longitudinallyextending channel 101 and the first section in each of the chambers.Further, one or more outlet openings 102 may extend between thelongitudinally extending channel and the exterior of the cushion. In oneembodiment, the outlet openings extend to an adjacent edge of the filmmaterial. Perforations 103 may be provided between the cushions for usein separating them.

FIG. 13 shows an example of a preconfigured film 421 as described in WO00/43198. The film 421 can be folded along its centerline to form aclosed edge 422 and an open edge 423. Transverse rows of perforations424 are formed at regular intervals along the length and extend acrossthe entire width of the material. The material is sealed together alongseal lines 426 formed on opposite sides of the perforations 424. Theseal lines extend from the closed edge 422 to within a short distancefrom the open edge 423. During inflation, air or other inflation gas isinjected between the two layers, and a machine seals the layers togetheralong a longitudinally extending seal line 428 to contain the air orother gas in the cushions.

FIG. 14 shows another example of a preconfigured film 500 that can beinflated through an open edge, as described in U.S. Pat. No. 6,982,113B2. The film has two layers 512 and 514 sealed to each other in apattern of seals 518, leaving unsealed areas which define the inflatablechambers 501 and inflation ports 524. The layers may be adhered by heatsealing or by use of an interposed adhesive. A pair of longitudinalflanges 530 are formed by the portion of the films 512 and 514 thatextend beyond the inflation ports 524 and intermittent seals 518. Thechambers 501 are inflated by injecting air through the flanges 530, andthen a longitudinal seal 552 is formed to close off the inflatedchambers 501.

The preconfigured film, such as any of the types shown in FIG. 1, 7, 13,or 14, may be wound into rolls or folded into boxes to form a supplythat can be used with the inflation and sealing apparatus.

One or more of the aforementioned aspects of the invention may beutilized in combination with existing machines for inflating and sealingpacking cushions, such as machines in which the path of the film can begenerally horizontal, e.g., as shown in Perkins U.S. Pat. No. 6,209,286,or generally vertical, e.g., as shown in Perkins U.S. Pat. No.6,659,150. An example of a machine that may be modified to include oneor more aspects of the invention is illustrated in FIGS. 2-6, which anapparatus for inflating and sealing a preconfigured film material asdescribed in U.S. Pat. No. 7,174,696. The apparatus may include arelatively small cabinet 31 which can be adapted to rest on a table topor other supporting surface. The cabinet has an L-shaped base 32 with anupstanding front wall 33, end walls 34, 36 and a removable cover 37 forthe top and rear sides of the cabinet.

In the apparatus shown in FIG. 2, a pair of spaced apart, horizontallyextending rollers 39, 41 may be disposed on the machine such as mountedon the upper side of the cabinet for receiving the roll of preconfiguredfilm material. The roll may be disposed to rest on the rollers and befree to rotate as the material is drawn from it. The gap between therollers is usually less than the diameter of the core so that the rollwill not drop between the rollers as it decreases in size. If desired,the axis of one or both of the rollers can be inclined slightly, e.g.,up to about 10 degrees, in order to keep the roll against a stop towardone side of the machine.

Again referring to FIG. 2, roller 39 may be rotatively mounted on astationary shaft 42 which extends between end walls 34, 36 near thefront the cabinet. Roller 41 may include two relatively short rollers 41a, 41 b mounted on a rotatively mounted shaft 43 to the rear of roller39. The rollers 41 a, 41 b may be positioned toward opposite sides ofthe machine for engagement with the roll of film material toward theedges of the roll. A roller 44 may be mounted on shaft 43 next to roller41 b and directly beneath longitudinally extending channel 19 in thepreconfigured film. A disk 46 is also mounted on shaft 43, with openings47 which may be detected optically to monitor rotation of the roll andthe removal of material from it.

In the apparatus shown in FIG. 2, a stop 49 may be located toward oneside of the cabinet and may be configured to as a guide for positioningthe roll on the rollers. Where a stop is used, the roll may be placed onthe rollers with the edge adjacent to the longitudinally extendingchannel 19 abutting against the stop 49 so that the channel 19 and theinlet openings 23 may be in the same position regardless of the width ofthe roll. As noted above, one or both of the rollers can be inclineddown toward the side of the cabinet where the stop is located to helpkeep the roll against the stop. With one or both of the rollers inclinedin this manner, they are still substantially horizontal, and the axis ofthe roll is still substantially parallel to the axes of the rollers. Theroll can be of any desired width, and it can even overhang the side ofthe cabinet opposite the stop as long as it is not so wide that theweight of the overhang causes the roll to tip or be unstable on therollers.

A drive mechanism 51, an elongate member 52 and a sealing assembly 53may be combined into a single modular unit 54 which may be locatedtoward the front of the machine. As shown in FIG. 3, the modular unit 54can be removably mounted on the outer side of end wall 36, and projectsthrough an opening 56 in that wall, with an end cover 57 and a frontcover 58 enclosing portions of it.

Still referring to FIG. 2, cover 58 may terminate just in front of thepath traveled by the film material in passing through the feed rollersand sealing assembly. A flange 81 may extend from the front wall of thecabinet in alignment with the left side of the cover and terminate justto the rear of the film path. The apparatus may also include guide shoes82, 83 mounted on the confronting edges of the cover and flange todefine an access opening 84 for the film material and to help guide thematerial into the feed rollers. Additionally, a guide 86 may bepositioned toward the front of the cabinet above the elongate member andfeed rollers to guide the film material toward them.

A control panel 87 may be located in any suitable position such as on aninclined portion of end cover 57 to the right of the drive module. Thispanel may include various controls such as controls for turning themachine on and off and for controlling various operational functionssuch as number and firmness of cushions being made. In addition, thecontrol panel 87 may include controls for adjusting various operatingparameters in response to data received from the supply of film, asdiscussed more fully below.

Operation and use of the machine can be described with reference to FIG.6. The roll of preconfigured film material 28 may be placed on rollers39, 41, with the longitudinally extending channel side of the roll 19abutting against stop 49, so that the longitudinally extending channelitself is aligned with nip roller 44 and elongate member 52. Other feedmechanisms, such as a cantilevered feed roll mechanism, also may beused.

Still referring to FIG. 6, the free end of the film material may bepulled down over guide 86 (shown in FIG. 3) and onto a guide such as theelongate member which extends into the longitudinally extending channel19. Once over the guide, it may be desirable for an operator to continueto pull down on the material until it engages the upstream feed rollersand is thereafter fed by the rollers. The guide or elongate memberperforms the function of guiding and keeping the film material properlyaligned with the rollers.

As the film material travels past the guide such as the elongate member,air or another suitable gas may be injected into the film using anysuitable mechanism either incorporated into the guide or separate fromthe guide. Where a gas is injected by the guide, it may be injectedusing a nozzle in the guide. Where air is injected from a location ornozzle disposed external to the guide, it may be preferable to positionthe source of the air injection port near the feed path of the film. Ineither case, a gas may be injected through openings such as openings 23,24 and into chambers such as the chambers 21, 22 discussed above. Thegas may be confined the portion of the film between the air injectionapparatus and where it is pinched off by roller 39 and/or roller 41 b.Depending upon the diameter of the roll, the film material may bewithdrawn from the roll at about 90 to 180 degree angle from the pointwhere the longitudinally extending channel is pinched closed by theroller.

The guide may be variously configured. In one embodiment shown in FIG.2, the guide includes an enlarged bulb 52 a at the upper end of anelongate member. The bulb 52 a may be configured to facilitate movementof the film material over the end portion of the elongate member and toprevent air from escaping back along the elongate member from thelongitudinally extending channel. A fitting 52 b may be provided at theother end of the elongate member for connection to an air pump.

With reference to FIGS. 3, 4, and 6, following inflation, the filmmaterial may be configured to travel through sealing assembly 53 whereroller 77 presses the material into contact with heating element 76. Thelayers of film material (e.g., two) may be fused together along arelatively narrow seal line 89 which may be configured to extendlongitudinally along the film material and across inlet openings 23 toseal the chambers.

The apparatus may be configured to utilize a slitting mechanism such asa knife to slit the film. For example, a slit may be formed in thechannel of the film. For example, the slitting mechanism may beconfigured to slit the film after the guide has been in contact with thefilm. The slitting mechanism may be positioned either before or afterthe air inlet. In one embodiment where the slitting mechanism ispositioned after the point in the apparatus where the cushion isinflated and sealed, the film material travels past the knife whichslits open the edge of the material next to the longitudinally extendingchannel so the elongate member can exit from the channel. Otherembodiments may slit the film before inflation. Still furtherembodiments may slit the film at the same time as inflation.

In embodiments where the feed rollers and the elongate member engageonly one edge portion of the film material, the machine can processmaterials of any desired width to make cushions having any desirednumber of chambers, including cushions having a single chamber thatextends the full width of the material.

The drive mechanism shown in FIG. 3 may include various guide rollerssuch as upstream rollers 61-64 and downstream rollers 66-69. Whereincluded, these rollers engage the edge portion of the film material andfeed it through the machine. The upstream and downstream rollers may bearranged in dual sets for engaging the film material on opposite sidesof the longitudinally extending channel. In these embodiments, upstreamrollers 61, 62 and downstream rollers 66, 67 engage the film materialbetween the longitudinally extending channel and the edge of thematerial, whereas upstream rollers 63, 64 and downstream rollers 68, 69engage it between the channel and the chambers. The feed rollers may bedriven by any suitable mechanism such as motor 71 which may be mountedinside the cabinet. The motor may include one or more drive gears,pulleys, or other suitable mechanisms on the motor shaft which may becoupled to driving gears 72, pulleys, or other suitable mechanismsaffixed to the shafts on which the rollers are mounted.

Elongate member 52 may be positioned between the inner and outer feedrollers and may extend in an upward direction. Optionally, it may curveinwardly as shown in FIGS. 2 and 3, for insertion into thelongitudinally extending channel of the film material. Air or anothersuitable gas may be supplied to the air injector, typically at apressure on the order of 0.5 to 10 psig by pump such as air pump 73. Thepump may also be mounted inside the cabinet. If desired, a regulator(not shown) can be connected between the pump and the air injector toallow users to adjust the air pressure and, hence, the degree offirmness to which the cushions are inflated.

In the device illustrated in FIGS. 3-5, the sealing assembly 53 may bepositioned between the upstream and downstream rollers. The sealingassembly may include one or more heating elements 76 and one or morebacking elements which press the film material against the heatingelement. The heating element may be mounted in a stationary position,and the roller may be mounted on a carriage 78. In this embodiment, theroller is pressed against the heating element by a cam 79 when themachine is operating, and withdrawn from the heating element when themachine is idle. This withdraw of the heating element from the backingelement while not in operation prevents the heating element from burningthe plastic and overheating the backing element. As shown in FIGS. 4 and5, the heating element may include a stainless steel rod 80 ofrelatively small (about ⅛ inch) diameter. The rod 80 may be configuredto extend vertically (or parallel to the direction of film travel) andperpendicular to the axis of the backing roller 77.

FIGS. 18 and 19 show an apparatus 200 a for inflating and sealingair-filled packing cushions in accordance with an alternative embodimentof the invention. Instead of having a guide roller 255 as previouslydescribed, a fixed guide member 256 is provided for guiding the filmfrom the supply to the belt drive assembly 218. The fixed guide member256 may be constructed of sheet metal or other suitable material such asa rigid plastic. As shown in FIGS. 18 and 19, the fixed guide member 256may have a generally curved exterior surface that surrounds or partiallysurrounds the roll of film material on the mandrel.

Also as shown in FIGS. 18 and 19, instead of having an adjustabletensioning mechanism such as nip roller 282 as previously described,apparatus 200 a has pair of compressed nip rollers 299 through which thefilm material is passed after it is unwound from the supply roll. Thenip rollers 299 may be covered with a resilient material, such asrubber, and may span the entire width of the film material. By nippingthe film material in this fashion, a constant approach angle of the filmmaterial is maintained to the inflation and sealing assembly, e.g., theapproach angle does not vary as the diameter of the film roll decreasesas the film material is unwound. Also, the location of the nip rollers299 as shown allows the inflatable gas to be injected into the chambersupstream all the way to the nip rollers 299, which in turn providesgreater pre-inflation volume and faster restart times between inflationcycles. After the film material passes between the nip rollers 299, itis fed over the exterior surface of the fixed guide member 256 to thebelt drive assembly 218.

As described in co-pending published application U.S. 2007/0251190 A1,the disclosure of which is hereby incorporated by reference in itsentirety, the apparatus may include a controller having functionalityfor acquiring information contained on the film or film supply, e.g.,such as a radio frequency identification (RFID) tag present on the filmor on a core on which a roll of film is wound. The information obtainedfrom the film or film supply can be used to set one or more operatingparameters for operation of the apparatus, such as seal temperature,seal pressure, air-fill levels, and operational timing delays in thedrive components. These and other operating parameters may be affectedby the thickness and composition of the film, the size and configurationof the inflatable chambers, and/or other properties of the film. Thecontroller optionally can be configured to write data back to the tag.For example, as described in published application U.S. 2007/0251190 A1,as the roll of film is processed the controller can periodically writeback to the tag the amount of film processed until all of the film isprocessed. This feature can be used to prevent a user from removing atag from an expired film supply and affixing the tag to a new supply ofmaterial that may be incompatible or unauthorized for use with theapparatus.

In some cases, users may want to have the capability of fine-tuningcertain operating parameters to meet user preferences. The controllercan be configured to permit users to adjust some or all of theparameters within preset limits. For example, the user may be permittedto adjust a value within +/−10% of a programmed value. Normally amid-range setting is selected for this programmed value to allow forslight user adjustments while preventing gross over-adjustments.Non-limiting examples of user-adjustable parameters include sealtemperature and air fill level.

The drive motor for the drive rollers 222 can be a fixed speed motor or,optionally, a variable speed motor. In the case of a variable speedmotor, the speed of operation can be adjusted by an operator enteringinformation on a keypad, or can be communicated from an RFID tag or thelike on the film supply.

As an alternative to RFID tags, the apparatus may utilize any number ofother techniques for transmitting data from a film or film supply to thecontroller. For example, the film or film supply can be printed with abar code or registration marks, or a label containing a bar code orregistration marks, or the like can be adhered to the film or filmsupply. The controller can retrieve the information from the film orfilm supply using a bar code reader or other appropriate reader.

With reference to the device shown in FIGS. 8-12, the controller can beadapted to control operation of one or more of the stepper actuator 230,the sealing element 216, the blower 225, the drive belts 218 a-218 c,and the roll unwind tensioning mechanism 282. The controller may beconfigured to be capable of adjusting one or more of sealing pressure,sealing temperature, air-fill level, tension on the film roll as it isunwound, and operational timing delays in the drive components. Sealingpressure can be controlled by controlling operation the stepper actuator230. Sealing temperature can be controlled by controlling the amount ofheat supplied to the sealing element 216. Air-fill level can becontrolled by controlling operation of the blower 225. Operationaltiming delays can be controlled by controlling operation of the variousdrive components. Tension on the film supply as it is unwound can becontrolled by controlling operation of the linear actuator 280. Each ofthese parameters can be controlled according to a predetermined schedulethat is appropriate for the particular film configuration used.

Operation of the perforation tear unit 250 may also be partially orfully automated. For example, the supply of film material may includeregistration marks that correspond to the location of the lateralperforations separating adjacent chambers or groups of chambers. Theapparatus may be equipped with an appropriate reader for sensing theregistration marks to enable the controller to determine the location ofthe perforations and appropriately control operation of the perforationtear unit 250. For example, when it is desired to tear the film along aperforation, the controller can cause the drive mechanism to advance thefilm, if needed, to position the perforation between the belt driveassembly 218 and the perforation tear unit 250, and then stop movementof the belt drive assembly 218. The nip rollers of the perforation tearunit may then be actuated to engage the film and pull it away from thestationary belt drive assembly 218, thereby tearing the film along theperforation. The perforation tear unit 250 may tear the film along aperforation upon a user-inputted request. Alternatively, the controllermay be programmed to actuate the perforation tear unit 250 to tear thefilm along perforations each time a predetermined number of adjacentcushions are inflated.

The preconfigured film may have any of the above-describedconfigurations, e.g., the film may be closed along both longitudinaledges or may be open along one longitudinal edge. The film may contain alongitudinal channel for receiving a guide and/or inflation member.Alternatively, the film may have an open edge through which air or othergas is injected to inflate the preconfigured chambers. The chambers maybe generally rectangular, circular, or other desired shape.

While particular embodiments of the present invention have beendescribed and illustrated, it should be understood that the invention isnot limited thereto since modifications may be made by persons skilledin the art. The present application contemplates any and allmodifications that fall within the spirit and scope of the underlyinginvention disclosed herein.

What is claimed is:
 1. An apparatus for inflating and sealing packingcushions from preconfigured film material having a plurality ofchambers, the apparatus comprising: a feed mechanism for feeding thefilm material along a path, the feed mechanism comprising a first beltwhich contacts a first surface of the film material in a first region,and a second belt laterally offset from the first belt such that thesecond belt contacts the first surface of the film material in a secondregion laterally offset from the first region; an inflation mechanismfor injecting inflation gas into the chambers; and a sealing mechanismcomprising a sealing element and a backing element, wherein the sealingelement contacts the first surface of the film material in a sealingregion located between the first region and the second region to form alongitudinal seal to trap inflation gas in the chambers.
 2. Theapparatus of claim 1 further comprising a linear actuator for adjustingthe position of the sealing element.
 3. The apparatus of claim 1 furthercomprising a thumbscrew for manually adjusting the position of thesealing element.
 4. The apparatus of claim 1 wherein the sealing elementcomprises a rotary sealing element.
 5. The apparatus of claim 1 whereinthe backing element comprises a belt.
 6. The apparatus of claim 1wherein the backing element is constructed from a resilient material. 7.The apparatus of claim 1 wherein the prefabricated film material has alongitudinally extending channel, the apparatus further comprising anelongate member adapted for insertion into the longitudinally extendingchannel.
 8. The apparatus of claim 7, wherein the elongate member has atleast one opening for injecting inflation gas into the longitudinallyextending channel.
 9. An apparatus for inflating and sealing packingcushions from preconfigured film material having a plurality ofchambers, the apparatus comprising: a feed mechanism for feeding thefilm material along a path, the feed mechanism comprising a first beltwhich contacts a first surface of the film material in a first region,and a second belt which contacts the first surface of the film materialin a second region; an inflation mechanism for injecting inflation gasinto the chambers; and a sealing mechanism comprising a sealing elementand a backing element, wherein the sealing element contacts a sealingregion of the film material to form a longitudinal seal to trapinflation gas in the chambers; wherein at least one of the first belt,the second belt, and the backing element has a crowned surface whichcontacts the film material and creates lateral tension in the sealingregion of the film material; wherein the backing element has a rib,wherein pressure from the sealing element creates a reactive force fromthe rib that deflects the backing element to flatten the film materialin the sealing region.
 10. The apparatus of claim 9 wherein each of thefirst belt, the second belt, and the backing element has a crownedsurface which contacts the film material and creates lateral tension inthe sealing region of the film material.
 11. The apparatus of claim 9wherein the backing element comprises a belt.